if desired, the compound of formula Vla can be converted to cis and trans 4-{3-l 3(R )-vinyl(or lower alkyl)- 4(R)-piperidyl]-propl-enyl}quinolines of formula Va, their antipodes or racemates utilizing a dehydrating agent such as thionyl chloride, phosphorus oxychloride, phosphorus pentachloride and the like, in the presence of an organic base, for example, a tertiary amine such as pyridine, trie